The present invention relates to a magnetostriction device for use with a magneto-machine transducer device such as a magnetostriction actuator and a magnetostriction piezoelectric transducer.
The magnetostriction device using magnetostrictive sintered material manufactured by the powder metallurgy method has a small volume density of approximately 80% as compared with a magnetostriction device manufactured by a single crystal method or a unidirectional solidification method. The reason for this is that this magnetostrictive sintered material has holes formed thereon and that these holes occupy approximately 20% of the whole volume of the magnetostrictive sintered material.
Therefore, the magnetostriction device using this magnetostrictive sintered material has a magnetic permeability smaller than that of the magnetostriction device manufactured by the single crystal method or the unidirectional solidification method. Furthermore, the above magnetostriction device using this magnetostrictive sintered material encounters a disadvantage that it is weak against external force such as when it is easily broken with application of pre-stress.